A city-state is a region controlled exclusively by a city. City-states were common in the ancient period. A city state was sovereign, although many cities were joined in formal or informal leagues under a high king. Many historical empires or leagues were formed by the right of conquest, (see: Mycenae; Rome,) but many were formed under peaceful alliances or mutual protection (see: Hanseatic League; Peloponnesian League.)
The tradition of Free Cities, independent of their surrounding terrain, which had been a medieval feature of the Holy Roman Empire, outlived the Empire's demise in 1806. In the 19th and 20th centuries, a variety of political and historic circumstances left several self-governing enclaves surrounded by the territory of another, in each case centered on a city. In Europe, they have included Fiume, Danzig, Memel and Trieste. On the edges of Europe they have included Batumi and Tangier. After 1870, the Vatican City has been a city-state.
The Adriatic port of Fiume on the Istrian peninsula, under Habsburg rule since 1466, was the main port of Hungary. Croats predominated in the city's population until the 19th century, when the Austro-Hungarian monarchy began to encourage Italian immigration as a counter-balance to the rise of Slavic nationalism.
Italy signed a secret treaty with the Allies in 1915, in which Italy was promised the Habsburg lands on the Adriatic in return for active military support of the Allied side. At the end of World War I, US President Woodrow Wilson believed the city should be given to the new Kingdom of Serbs, Croats and Slovenes.
The Italians felt bitterly cheated out of what had been promised to them for their participation in the war. The Fascist and poet Gabriele D'Annunzio organized a paramilitary force of demobilized soldiers and thugs, the Arditi, whom he dressed in black shirts. On September 12, 1919, D'Annunzio led the Arditi into Fiume and seized control of the city.
D'Annunzio was proclaimed dictator. He remained dictator of Fiume until December 1920, when the Italian government sent a battleship into Fiume to bombard the municipal palace.
D'Annunzio surrendered, and Fiume was proclaimed a "Free State" under a provisional government. Mussolini, emboldened by D'Annunzio's temporarily successful seizure of Fiume, marched on Rome with his own Fascist "black shirts" and seized control of the Italian government in March 1922. Local Fascists seized control of Fiume at the same time.
In 1924 Mussolini negotiated the Treaty of Rome by which the Kingdom of Serbs, Croats and Slovenes ceded Fiume to Italy. The city was formally annexed to Italy on March 16, 1924.
Fiume was occupied by the Germans in 1943 and was liberated by Yugoslav partisans in 1945. After World War II, the Italian population was evacuated and the city was ceded to Yugoslavia. Today, it is the Croatian city of Rijeka.
Danzig, as the Germans called it (the city is Gdansk in Polish, on the Baltic Sea in West Prussia, had an overwhelmingly German population of about 400,000 and was a special case. The re-emergence of a Polish nation after World War I left large German minorities living in Polish territory. West Prussia became the Polish Corridor to the Baltic Sea, cutting East Prussia off from the rest of Germany
The League of Nations compromise that created Danzig a free city (1920–39) satisfied neither the Poles (who needed the city's port facilities) nor the German population, who wanted to remain a part of a Greater Germany.
Resentment over the status of Danzig helped bring Hitler to power. On September 1, 1939, Germany invaded Poland, and Danzig was temporarily restored to Germany. In December 1943 the city was occupied by the Red Army. The German population was largely expelled to Germany, and the city was made the Polish city of Gdansk.
Memel offered a comparable situation, with the historically German port city of Memel, founded in 1252 by the Teutonic Knights on the Baltic Sea, a holdover of the Hanseatic League, isolated within Lithuanian territory.
Memel was detached from Germany by the Treaty of Versailles and was governed by an Allied and Associated Powers Commission.
In January 1923, Lithuania invaded Memel and expelled the French garrison without a fight. In 1924 the League of Nations acknowledged the fait accompli, and Memel was incorporated into Lithuania as a semi-autonomous district.
In March 1939, Hitler sent German warships to Memel and delivered an ultimatum to Lithuania to surrender the city or face war. The Lithuanians surrendered, in Hitler's last bloodless conquest before World War II. After the war, the German population was expelled, and the city was returned to Lithuania. Today it is the Lithuanian city of Klaipeda.
The Adriatic port of Trieste, in the province of Venezia Giulia, was the chief port of Austria prior to World War I.
The population of the region was predominantly Italian. The Italian army conquered Venezia Giulia during WWI, and it became part of Italy after the war.
At the end of WWII in May 1945, Yugoslav troops captured the city. After the war, Trieste and the surrounding territory became the Free Territory of Trieste under United Nations protection during 1947–54. The territory was divided into Zone A, which included the city of Trieste and was under Allied control administered by the United States and United Kingdom, and Zone B, the surrounding territory, controlled by Yugoslavia. In 1954, Zone A reverted to Italy, while Zone B became a part of the Yugoslavian republic of Slovenia.
After King Victor Emmanuel II of Italy seized Rome in 1870, Pope Pius IX refused to acknowledge the existence of the Kingdom. Because he could not travel through a place that he did not admit existed, Pius IX and his successors each became "the Prisoner in the Vatican", unable to leave the 0.17 square mile (440,000 m ) papal enclave once they ascended the papal throne.
The impasse was resolved in 1929 by the Lateran Treaties negotiated by Benito Mussolini between Victor Emmanuel III and Pope Pius XI.
Under this treaty, Vatican City was recognized as an independent state with the pope as its head. Vatican City has its own citizenship, diplomatic corps, flag, currency, and postal system.
Batumi is a seaport on the Black Sea and is the capital of Adzaristan, now an autonomous republic in the Republic of Georgia. The Adzaris converted to Islam after being conquered by the Ottoman Empire in the 18th century. Russia annexed Adzaristan in 1878 but the Ottomans retook it during World War I. In 1918, British forces took the petroleum port of Batum from the Ottomans and declared it a free port. As Allied intervention in Russia wound down, the city was taken by the Bolsheviks after the British withdrew in 1920.
When the Sultanate of Morocco was divided into French and Spanish zones under the Treaty of Fez in 1912, Tangier was given special status. The Convention of 1923 made Tangier an international city governed by a legislative assembly of 26 foreign representatives from Britain, France, Spain, Portugal, Italy, Belgium, Netherlands, Sweden and the United States. Executive power was vested in the Committee of Control composed of the consuls of the signatory powers.
Mixed courts with French, Spanish, British and Belgian judges administered justice. Arabs and Jews had their own separate court systems. Foreign powers operated a number of postal systems in the city, and Spain, France and Britain issued stamps for Tangier.
Today the term can refer to the independent states of Monaco and Singapore, as well as subnational units such as the German states of Berlin, Bremen and Hamburg, the Austrian capital Vienna and Russian cities of Moscow and Saint Petersburg. Countries that have a very high proportion of their population within a single city are sometimes referred to as virtual or near city-states. Kuwait is one such example. In China, the term is sometimes used for the Special Administrative Regions of Hong Kong and Macau.
The many poleis of ancient Greece are classical examples. Other examples of city-states in history include: